# -*- coding:utf-8 -*-
# @Time   :  15:18
# @Author : jinzhongyi
# @File   : tk2_label_button.py

import tkinter as tk

window = tk.Tk()
window.title('my window')
window.geometry('200x100')

var = tk.StringVar()
l = tk.Label(window, textvariable = var, bg = 'green', font=('Arial', 12),
             width=15, height=2)
l.pack()

on_hit = False
def hit_me():
    global on_hit
    if on_hit == False:
        on_hit = True
        var.set('you hit me')
    else:
        on_hit = False
        var.set('')
b = tk.Button(window, text = 'hit me', width = 15,
              height = 2, command=hit_me)
b.pack()
window.mainloop()